1. Field of the Invention
The present invention relates to a color filter substrate, a liquid crystal display panel, liquid crystal display apparatus and a method of manufacturing the color filter substrate. More particularly, the present invention relates to a color filter substrate having enhanced luminance, a liquid crystal display panel, liquid crystal display apparatus having the color filter substrate, and a method of manufacturing the color filter substrate for reducing cost.
2. Description of the Related Art
A liquid crystal display apparatus includes an array substrate having a thin film transistor, a color filter substrate and a liquid crystal layer interposed between the array substrate and the color filter substrate. Liquid crystal material in the liquid crystal layer has anisotropic dielectric constant and anisotropic transmittance. Thus, when electric fields are applied to the liquid crystal layer, liquid crystal molecules in the liquid crystal layer are rearranged, so that transmittance of a light is adjusted to display an image.
Generally, liquid crystal material does not emit a light. Thus, the liquid crystal display apparatus uses an ambient light or a light generated from an internal device of the liquid crystal display apparatus to display an image.
When the liquid crystal display apparatus of a mobile equipment uses only light generated from an internal device, a size of a battery for supplying power increases, leading to increase a size of the mobile equipment. When the liquid crystal display apparatus uses only an ambient light, the liquid crystal display apparatus may not display an image in a dark place. However, when the liquid crystal display apparatus uses both the light generated from the internal device and the ambient light, problems of above may be solved.
General reflective transmissive type liquid crystal display apparatus includes a liquid crystal display panel, an optical film assembly and a backlight assembly.
The liquid crystal display panel includes a color filter substrate, an array substrate and a liquid crystal layer. The color filter substrate includes a color filter and a common electrode. The array substrate includes a reflective electrode, a transparent electrode and a thin film transistor. The liquid crystal layer is interposed between the array substrate and the color filter substrate. The optical film assembly includes a polarizer and a compensating film. The backlight assembly is disposed under the liquid crystal display panel to provide the liquid crystal display panel with light.
The liquid crystal may be aligned in various ways. Thus, the liquid crystal display apparatus may be classified into twisted nematic (TN) mode, super twisted nematic (STN) mode, mixed twisted nematic (MTN) mode, vertical alignment (VA) mode or electrically controlled birefringence (ECB) mode in accordance with an alignment of the liquid crystal.
The color filter allows a light having a wavelength corresponding to a color of the color filter to pass through the color filter. Thus, when a light passes through the color filter, a luminance decreases.
An external light that enters the liquid crystal display apparatus passes through the color filter and the liquid crystal layer to be reflected on the reflective electrode. Thus, the reflected light passes through the liquid crystal layer and the color filter again to exit the liquid crystal display apparatus. Thus, the external light passes through the liquid crystal layer and the color filter twice.
A light generated from the backlight assembly passes through the transparent electrode, the liquid crystal layer and the color filter to exit the liquid crystal display apparatus. Thus, the light generated from the backlight assembly passes through the liquid crystal layer and the color filter once.
When a light passes through color filter, a luminance of the light decreases. Thus, the luminance of the light that is reflected from the reflective electrode is lower than the luminance of the light that passes through the transparent electrode.
Korea Laid Open Patent Publication number 2001-0055636 discloses a color filter substrate including a color filter that has different thickness. That is, the color filter has first and second portions corresponding to the transparent electrode and the reflective electrode, respectively, and the first portion is thicker than the second region.
However, the light reflected from the reflective electrode passes through the liquid crystal layer twice, and the light passing through the transparent electrode passes trough the liquid crystal layer once. Thus, an optical condition of the light reflected from the reflective electrode is different from the optical condition of the light that passes through the transparent electrode, so that a display quality is deteriorated.